This invention is generally directed to a print element control for causing dots to be selectively printed across a line of print on a print medium as the print elements execute a traversal across the line of print. It is more particularly directed to selectively actuating desired print elements of a shuttle printer having a plurality of such print elements each of which are caused to traverse a plurality of respective dot columns along a single dot row at a sinusoidal velocity.
Shuttle dot matrix type apparatus is already known in the art. For example, a related commonly assigned copending application to Caulier Ser. No. 438,928, filed Nov. 3, 1982, now abandoned as well as commonly assigned copending application to Miller Ser. No. 531,648 filed Sept. 13, 1983, now U.S. Pat. No. 4,637,307 describes a balanced print head drive mechanism for operating a shuttle printer at a sinusoidal velocity. The contents of these earlier related applications are hereby expressly incorporated by reference.
Certain of such shuttle printers use a velocity sensor and contemplate driving the system at the natural, mechanical, resonant frequency of the shuttle printer. Serious challenges are posed under such circumstances for precisely controlling the actuation of individual printing elements moving across a line of print during shuttling action, particularly when the shuttling action is non-constant. If the control is not precise, damage to component parts as well as smearing and unacceptable printing and deterioration of the components takes place.